I'm wondering why the various SAE Viscosity Grade charts I can find don't correspond with the SAE J300 minimum KV100 (cSt) for SAE 20 grade oil.
The other Viscosity Grade minimums specified for KV100 are pretty close for 30, 40 and 50 grades ... so that might just be due to "sloppy" chart makers (?). But SAE 20 grade seems to be off compared to SAE J300 in every chart I can find. See the examples below. Any reason why?
Is it because of this flag note in the SAE Viscosity Grade chart? If so, isn't the SAE J300 minimum KV100 specs based on something similar?
Note that the 2015 version of SAE J300 shown below is the most current version.
J300 Minimum KV100 for SAE Grades
SAE 20 - 6.9 cSt
SAE 30 - 9.3 cSt
SAE 40 - 12.5 cSt
SAE 50 - 16.3 cSt
In both SAE Viscosity Grade Charts below, the blue lines show the minimum KV100 value called out in SAE J300.
The red lines show the values that correspond to the minimum KV100 in the viscosity grading graph.
The SAE 20 in both charts show the minimum KV100 to be quite a bit lower than the J300 specification.
The lower end of SAE 20 in both of these charts is in the 5.7-5.8 cSt range when SAE J300 calls out 6.9 cSt. Why ??
The KV100 in SAE J300 and in this SAE Viscosity Chart are basically the same at 9.3 cSt, but again for SAE 20 they are way off.
The other Viscosity Grade minimums specified for KV100 are pretty close for 30, 40 and 50 grades ... so that might just be due to "sloppy" chart makers (?). But SAE 20 grade seems to be off compared to SAE J300 in every chart I can find. See the examples below. Any reason why?
Is it because of this flag note in the SAE Viscosity Grade chart? If so, isn't the SAE J300 minimum KV100 specs based on something similar?
Note that the 2015 version of SAE J300 shown below is the most current version.
J300 Minimum KV100 for SAE Grades
SAE 20 - 6.9 cSt
SAE 30 - 9.3 cSt
SAE 40 - 12.5 cSt
SAE 50 - 16.3 cSt
In both SAE Viscosity Grade Charts below, the blue lines show the minimum KV100 value called out in SAE J300.
The red lines show the values that correspond to the minimum KV100 in the viscosity grading graph.
The SAE 20 in both charts show the minimum KV100 to be quite a bit lower than the J300 specification.
The lower end of SAE 20 in both of these charts is in the 5.7-5.8 cSt range when SAE J300 calls out 6.9 cSt. Why ??
The KV100 in SAE J300 and in this SAE Viscosity Chart are basically the same at 9.3 cSt, but again for SAE 20 they are way off.
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